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Shadows Indicates if the light is casting a shadow.
Hotspot Angle (Spotlight and Freespot only) Specifies the angle of the
brightest cone of light.
Falloff Angle (Spotlight and Freespot only) Specifies the outer extremity of
the light, where it meets the darkness.
Intensity Factor Magnifies the effect of the skylight.
Filter Color Specifies the secondary color of the light. Represents the color of
a physical filter over the lamp. Default color is white.
When lighting is set to photometric units this represents a secondary color
filter on the light. When lighting is set to generic lighting this represents the
total color of the light.
Plot Glyph Allows the ability to plot the drawing with the glyphs on.
Photometric Properties
The following property settings are available:
Lamp Color Specifies the inherent color of the light in Kelvin temperature
or standard.
Resulting Color Reports the final color of the light. This is determined by a
combination of the Lamp Color and the Filter Color. (Read-only)
Intensity Method Specifies the value in which light intensity should be
measured.
 Intensity (Candela). Specifies the number of candelas (cd) is the SI unit
of luminous intensity (perceived power emitted by a light source in a
particular direction).
 Flux (Lumen). Represents the rate of total energy leaving the lamp. It is
specified in lumens (SI and American). Mathematically, the flux is the
integral of the luminous intensity over the sphere. The calculation of flux
depends on the distribution of intensities. For a point light with constant
intensity, the flux is simply the product of the intensity and the solid angle
of a sphere: 4 Pi * Intensity. For a spot light, the flux is the product of the
intensity and the solid angle of the hotspot cone, plus the incremental
solid angle of the fall-off region. For a weblight, there isn’t any analytical
formula. The flux is obtained by numerically integrating the intensities
provided in the web file.
 Illuminance (Foot-candles). Represents the energy per area arriving at
a surface (Area-flux-density). It is specified in lux (SI) and foot-candles
(American). For a near light, because the light rays are diverging, you have
to talk about the illuminance at a specific distance from the lamp. So this
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